Photoelectric tube



April 19, 1938. P. GRmcH PHOTOELECTRIC TUBE Filed Aug.r 6, 195e Patented Apr. 19, 1.938

UNITED STATES PATENT OFFICE PHOTOELECTRIC TUBE many Application August 6, 1936, SerialV No. 94,590 In Germany August 28, 1935 1 Claim.

The invention relates to improvements in photo electric tube and particularly pertains to a novel construction of a tube which is adapted to make full use of the action of the secondary emission of 5 electrons.

It is known that the emission of electrons of a photo electric tube of this type can be substantially increased by causing the electrons emitted by the primary cathode due to incident light to impinge with suflicient speed upon a secondary cathode, which then emits substantially more electrons than have been received by the same.

It is now an object of the invention to mount and secure the cathodes in such a manner within the tube that the insulation value of the primary cathode with respect to the secondary cathode is as high as practically possible. With this object in View, the photo electric tube of the present invention is provided with a lead-in wire for the primary cathode which does not pass through the same fusion point of the tube vessel through which passes the lead-in wire for the secondary cathode. In fact, it is a very important object of the invention to place the two fusion points through which the respective cathode lead-in Wires enter the tube as far apart as possible, so that the insulation-resistance between the two lead-in wires is suciently high to prevent any disturbances during the operation of the tube.

In the drawing the Figs. 1 to 6 illustrate diagrammatically various embodiments of the invention.

Fig. 1 shows a tube in which the lead-in wire for the primary cathode PK passes at a through the side wall of the Vessel V, while the lead-in wire for the secondary cathode SK enters the top portion of the vessel V at bl. The lead-in wire for the anode A passes at c through the bottom portion of the vessel.

In Fig. 2 the lead-in wire for the primary cathode PK enters the top portion of the Vessel V (Cl. Z-27.5)

at d, while the lead-in wire for the secondary cathode SK passes at e through the side wall of the vessel. The lead-in wire for the anode A, as in Fig. 1, passes through the bottom ofthe vessel at f.

In the tube illustrated by Fig. 3 the lead-in wire for the primary cathode PK and the one for the anode A enter the vessel V both from the bottom as indicated by g and h respectively, While the lead-in wire for the secondary cathode SK 10 passes at i through the top wall of the vessel V.

In Fig. 4, the lead-in wire for the primary cathode PK enters the side Wall of the vessel V at 1c, the lead-in wire for the secondary cathode SK enters the vessel through the bottom wall at Z, 15 while the anode A is connected to a lead-in Wire passing at m through the top wall of the vessel.

Fig. 5 shows a photo electric tube in which the lead-in wire for the primary cathode PK enters the vessel V through its bottom at n, While 20 the secondary cathode SK is connected to a leadin wire passing through the side wall at 0. The anode A is connected to a lead-in wire entering the vessel V from the top as shown at p.

According to Fig. 6 the lead-in wire for the 25 primary cathode PK passes at r through the top wall of the vessel V, and the lead-in wires for the secondary cathode SK and for the anode A respectively are both entering the vessel V through the bottom wall thereof as indicated at s and t 30 respectively.

I claim as my invention:

A photo electric tube comprising a vessel, a primary cathode, a secondary cathode and an anode within said vessel, a lead-in wire entering 35 said vessel from above and connected to said secondary cathode, and two lead-in wires entering said vessel from below and connected to said primary cathode and said anode respectively.

40 PAUL GORLICH. 

